LCD devices are commonly used as display devices for compact electronic apparatuses. This is because LCD devices not only provide good quality images, but also are very thin and consume little power. The liquid crystal in a liquid crystal display device is not capable of emitting light by itself. The liquid crystal has to be lit by a light source so as to clearly and sharply display text and images. Thus, a backlight module for an LCD is generally needed.
FIG. 9 is an exploded, isometric view of a typical backlight module. The backlight module 1 includes a light guide plate (LGP) 11, a light source 13, and a set of optical films 15 disposed on the LGP 11. The LGP 11 includes a top light emitting surface 111, a bottom surface 113, and a side light incident surface 115. The light source 13 is located adjacent to the light incident surface 115. The light source 13 includes a cold cathode fluorescence lamp (CCFL) 131, a U-shaped reflector 133 partially enclosing the CCFL 131, and two rubber blocks 135 engaged with two ends of the CCFL 131 respectively.
In FIG. 10, an exploded, side view of the backlight module 1 is shown. The two parallel sidewalls of the U-shaped reflector 133 are engaged with end portions of the light emitting surface 111 and the bottom surface 113 respectively, in order to hold the U-shaped reflector 133 in place at an end of the LGP 11. The two rubber blocks 135 are fittingly engaged in two ends of the U-shaped reflector 133, and contact the light incident surface 115 of the LGP 11.
If the LGP 11 sustains shock or undergoes vibration, only the two rubber blocks 135 absorb mechanical force that transmits from the LGP 11 to the CCFL 131. Thus, when the backlight module 1 experiences shock, the CCFL 131 is liable to be damaged. In addition, if the U-shaped reflector 133 becomes distorted, light beams emitted by the CCFL 131 may leak out from the backlight module 1. This leads to a decrease in the light utilization efficiency of the backlight module 1. Furthermore, because the set of optical films 15 is close to the light source 13, during operation of the light source 13 the surrounding temperature of the light source 13 rises. This may result in the set of optical films 15 becoming too hot and distorting.
What is needed is a backlight module and an LCD device with the backlight module which can overcome the above-described deficiencies.